Cytokines and Madness: A Unifying Hypothesis of Schizophrenia Involving Interleukin-22

• DOI: 10.20944/preprints202411.0219.v1
• Publication Date: 2024-11-06T00:52:06Z
• Authors: Adonis Sfera; Kyle A. Thomas; Jacob Anton
• Keywords: 0301 basic medicine; 03 medical and health sciences; Review

Schizophrenia is a severe neuropsychiatric illness of uncertain etiopathogenesis in which antipsychotic drugs can attenuate the symptoms, but patients rarely return to the premorbid level of functioning. In fact, with each relapse, people living with schizophrenia progress toward disability and cognitive impairment. We hypothesize that poor outcomes in schizophrenia reflect gray matter volume reduction, which continues despite treatment. We further hypothesize that aryl hydrocarbon receptor phosphorylates signal transducer and transcription-three protein, suppressing the gut barrier protectors, including brain-derived neurotrophic factor and interleukin-22. We construe that recombinant human IL-22 can improve schizophrenia outcome by the following actions: 1. Averting microbial translocation outside the gastrointestinal tract by optimizing the gut barrier permeability. 2. Upregulation of BDNF, a neurotrophin lowered in schizophrenia. 3. Downregulation of interferon-gamma, a cytokine elevated in patients with schizophrenia. 4. Acceleration of wound healing and long-term memory formation via STAT3-induced inflammatory responses. This short review examines the influence of IL-22 and BDNF on the STAT3 /AhR axis. Based on the hypothesis described here, we discuss alternative SCZ interventions, including aryl hydrocarbon receptor antagonists, mitochondrial transplant, membrane lipid replacement, and recombinant human IL-22.